Udder shape and teat-end lesions as potential risk factors for high somatic cell counts and intra-mammary infections in dairy cows.
The association of common bacterial pathogens in milk samples during calving with udder shape or the presence of 'teat-end' lesions was investigated in 240 dairy cows from two herds. Sixty-three of 120 cows (53%) in one herd (herd A) and 54/120 animals (45%) in a second herd (herd B) had normal-shaped udders. The remaining animals had udder shapes defined as follows: large pendulous (18% herd A, 26% herd B); large between hindquarter (10% herd A, 17% herd B); overall small (8% herd A, 5% herd B); or small but pendulous (11% herd A, 7% herd B). At calving teat-end lesions were present in 63% and 76% of the quarters of herd A and B animals, respectively. There was no herd effect on udder shape or teat-end lesions. Analysis of variance revealed that udder shape and teat-end lesions did not have a significant association with quarter somatic cell count. However there was some association between mammary infection and udder shape and teat-end lesions. Compared to other udder shapes, cows with large between hindquarter shape had significantly less Staphylococcus aureus and Streptococcus uberis infection (P<0.001). There was a similar albeit less significant negative association with Escherichia coli infection (P<0.01). Infection with Streptococcus agalactiae and Streptococcus dysgalactiae was more frequent in cows with large pendulous and overall small udder conformations. The results also suggest an association between intra-mammary infection at calving and the presence of hyperkeratotic teat-end lesions, given that S. aureus, coagulase-negative staphylococci, S. uberis, S. agalactiae and E. coli were cultured from significantly more quarters with such lesions than from quarters without lesions or with other types of lesion (P<0.001).
Bhutto
Abdul L
AL
Department of Veterinary Clinical Sciences, University of Liverpool Veterinary Teaching Hospital, Leahurst, Neston, Wirral CH64 7TE, UK.
Murray
Richard D
RD
Department of Veterinary Clinical Sciences, University of Liverpool Veterinary Teaching Hospital, Leahurst, Neston, Wirral CH64 7TE, UK.
Woldehiwet
Zerai
Z
Department of Veterinary Pathology, University of Liverpool Veterinary Teaching Hospital, Leahurst, Neston, Wirral CH64 7TE, UK. Electronic address: zerai@liverpool.ac.uk.
D000704:Analysis of Variance; D000818:Animals; D002417:Cattle; D002452:Cell Count / Q000662:veterinary; D003612:Dairying; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D005260:Female; D008321:Mammary Glands, Animal / Q000033:anatomy & histology* / Q000382:microbiology / Q000473:pathology*; D008414:Mastitis, Bovine / Q000453:epidemiology* / Q000382:microbiology*; D008892:Milk / Q000166:cytology / Q000382:microbiology; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology / Q000662:veterinary; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology / Q000662:veterinary